Manufacturing method of lower rail of seat slider device

Abstract

A seat slider device may include a lower rail attachable to a body of a vehicle; and an upper rail attachable to a lower portion of a seat and slidably engaging with the lower rail. The upper rail may include a lock pin movable along a short direction of the upper rail. The lower rail may include a plurality of first holes and a second hole. The first holes may be arranged along a longitudinal direction of the lower rail and configured to engage with the lock pin, and the second hole may be arranged with the first holes along the longitudinal direction of the lower rail. The second hole may be positioned at a position where the lock pin is incapable of engaging with the second hole or the second hole may have a size with which the lock pin is incapable of engaging.

What is claimed is: 
     
       1. A method of manufacturing a lower rail of a seat slider device having an upper rail slidably engaging with the lower rail, wherein the upper rail includes lock pins arranged in line along a longitudinal direction of the lower rail, the method comprising:
 forming a first group of holes, a second group of holes, and a third group of holes in a plate that has an overall length along the longitudinal direction, wherein
 the first group of holes is formed between the second group of holes and the third group of holes, 
 the first group of holes, the second group of holes and the third group of holes together are distributed along the overall length, 
 the first group of holes are formed with a size and an interval that allows the lock pins to be engaged with the first group of holes, wherein
 the second group of holes and the third group of holes are not aligned with the first group of holes, 
 the second group of holes and the third group of holes are arranged at different intervals from the interval of the first group of holes, or 
 the second group of holes and the third group of holes are smaller than tips of the lock pins, such that the lock pins are incapable of engaging with the second group of holes and the third group of holes; and 
 
 
 bending the plate to include
 a bottom plate section, 
 a pair of outer vertical plate sections respectively extending upward from both ends of the bottom plate section in a rail short direction, 
 a pair of upper plate sections respectively extending laterally from upper ends of corresponding outer vertical plates toward a center in the rail short direction, and 
 a pair of inner vertical plate sections respectively extending downward from inner ends of corresponding upper plates, wherein the first group of holes, the second group of holes and the third group of holes are within at least one of the pair of inner vertical plate sections. 
 
 
     
     
       2. The manufacturing method of  claim 1 , wherein the second group of holes and the third group of holes are not in either of the pair of upper plate sections. 
     
     
       3. The manufacturing method of  claim 1 , wherein the second group of holes includes more than two holes and the third group of holes includes more than two holes.